This research project is a study of approximately 100 obese human subjects. The patients are selected to include those with various degrees of severity and various ages of onset. Various modes of treatment in an outpatient setting (nutritional, psychotherapeutic and behavioristic) are evaluated. During brief hospitalization there are detailed studies of adipose cellularity, carbohydrate tolerance and the behavioral consequences of obesity and weight reduction. Behavioral studies evaluate the frequency and severity of depressive changes as well as body image and time sense disturbances following weight reduction. The frequency of insensitivity to internal signals for hunger and satiety are evaluated by studies of taste preference and social psychological experiments, involving the decision to eat in a variety of experimental settings.